let getUserIP = function(onNewIP) { // 获取ip地址
  let MyPeerConnection = window.RTCPeerConnection || window.mozRTCPeerConnection || window.webkitRTCPeerConnection
  let pc = new MyPeerConnection({iceServers: []})
  let noop = function () {}
  let localIPs = {}
  let ipRegex = /([0-9]{1,3}(\.[0-9]{1,3}){3}|[a-f0-9]{1,4}(:[a-f0-9]{1,4}){7})/g
  function iterateIP (ip) {
    if (!localIPs[ip]) onNewIP(ip)
    localIPs[ip] = true
  }
  pc.createDataChannel('')
  pc.createOffer().then(function (sdp) {
    sdp.sdp.split('\n').forEach(function (line) {
      if (line.indexOf('candidate') < 0) return
      line.match(ipRegex).forEach(iterateIP)
    })
    pc.setLocalDescription(sdp, noop, noop)
  }).catch(function (reason) {
    // An error occurred, so handle the failure to connect
  })
  // seen for candidate events
  pc.onicecandidate = function (ice) {
    if (!ice || !ice.candidate || !ice.candidate.candidate || !ice.candidate.candidate.match(ipRegex)) return
    ice.candidate.candidate.match(ipRegex).forEach(iterateIP)
  }
}
export default getUserIP